[Support] Use static_assert instead of assert (NFC)

Identified with misc-static-assert.

GitOrigin-RevId: 2d5eb67235c763898f7c3327fb97b1ae1307d8e4
diff --git a/lib/Support/SHA256.cpp b/lib/Support/SHA256.cpp
index a3a6af2..3b81506 100644
--- a/lib/Support/SHA256.cpp
+++ b/lib/Support/SHA256.cpp
@@ -204,7 +204,7 @@
   // Fast buffer filling for large inputs.
   while (Data.size() >= BLOCK_LENGTH) {
     assert(InternalState.BufferOffset == 0);
-    assert(BLOCK_LENGTH % 4 == 0);
+    static_assert(BLOCK_LENGTH % 4 == 0, "");
     constexpr size_t BLOCK_LENGTH_32 = BLOCK_LENGTH / 4;
     for (size_t I = 0; I < BLOCK_LENGTH_32; ++I)
       InternalState.Buffer.L[I] = support::endian::read32be(&Data[I * 4]);